Recent analysis of 1980-81 National Ambulatory Medical Care Survey (NAMCS) data has found that close to 9 out of 10 elderly persons receiving mental health services from office-based physicians are being treated by physicians not formally trained in psychiatry (Schurman et al., 1983). Given that non-psychiatrist physicians represent such an important source of mental health care for the elderly, it is of interest to know more about the content and quality of care they are providing. Results from this study will have important implications for modifying future training protocols for incoming medical students, and for developing continuing medical education courses for practicing physicians, to increase practitioners' awareness of the special health needs of older persons. Eight years' worth of NAMCS data (1974-81) will provide the data base for this study. All physicians' mental health visits furnished to elderly persons during this time period will be analyzed. A host of descriptive analyses are proposed, addressing questions in four separate areas: 1) changes in the content of mental health visits over time; 2) characteristics of patients receiving mental health services from psychiatrists vs. other physicians; 3) characteristics of physicians providing mental health care; and 4) psychotropic drug prescribing practices for the elderly. Several multivariate analyses are also planned for this study which explore changes in access to private-practice psychiatrists' services over time, and factors affecting the choice of treatment modalities for the elderly. In the first instance, our objective is to identify those factors which raise (lower) the probability that an elderly person will receive mental health services from a physician trained in psychiatry, and also to determine whether access to ambulatory psychiatric care has improved since the mid-seventies. The second component of the multivariate analysis explores physicians' choice of treatment modalities for elderly patients, and the extent to which physicians substitute drug therapy for more time-intensive counselling services (e.g., psychotherapy).